fluoranthene+CH3 C17H12

A2_048ea73dab · SMILES Cc1ccc2c3c(cccc13)-c1ccccc1-2 · InChIKey XHJKUHDKEFRGSK-UHFFFAOYSA-N

Cheap level done

finite-difference Hessian noisy

finite-difference Hessian noisy (analytic check differs > 15 cm⁻¹). The finite-difference Hessian and the analytic Hessian of the same geometry differ by more than 15 cm⁻¹ on at least one frequency; the numerical route is the noisy one.

Harmonic frequencies at the cheap level (deck v1: B3LYP and ωB97X, 6-31G*, at the B3LYP geometry)

81 vibrational modes; imaginary modes negative. Shift = ωB97X − B3LYP.

Band heights are not computed for this molecule yet (no dipole derivatives); positions only, at unit height. High wavenumbers on the left; the table below is the same data.

#	B3LYP (cm⁻¹)	ωB97X (cm⁻¹)	shift
1	81.0	85.0	+4.0
2	120.0	118.3	-1.7
3	138.6	134.8	-3.8
4	166.1	170.8	+4.7
5	183.7	196.1	+12.3
6	192.2	198.4	+6.1
7	281.5	283.6	+2.1
8	284.9	290.6	+5.7
9	348.6	354.8	+6.2
10	356.9	358.7	+1.8
11	442.4	448.6	+6.2
12	459.4	464.0	+4.6
13	466.9	475.5	+8.7
14	471.9	481.5	+9.6
15	540.7	548.8	+8.1
16	555.8	559.2	+3.4
17	571.0	572.3	+1.3
18	578.3	591.7	+13.5
19	599.3	602.2	+2.9
20	648.6	658.5	+9.8
21	666.3	676.9	+10.6
22	681.4	687.6	+6.2
23	727.5	733.0	+5.6
24	760.0	772.5	+12.5
25	772.8	784.8	+12.0
26	796.0	807.4	+11.5
27	803.7	808.5	+4.8
28	833.9	847.7	+13.7
29	852.0	861.2	+9.2
30	858.1	870.8	+12.7
31	887.4	907.3	+19.9
32	915.9	947.1	+31.2
33	935.7	951.3	+15.6
34	943.3	966.0	+22.7
35	943.7	970.3	+26.6
36	969.8	1001.7	+32.0
37	976.1	1009.7	+33.6
38	1005.3	1010.4	+5.1
39	1048.8	1055.5	+6.7
40	1054.9	1062.1	+7.2
41	1074.8	1079.4	+4.6
42	1087.8	1095.9	+8.1
43	1109.2	1121.0	+11.8
44	1123.9	1123.7	-0.3
45	1179.4	1181.1	+1.7
46	1183.5	1187.2	+3.8
47	1194.1	1190.6	-3.5
48	1218.1	1215.8	-2.3
49	1245.7	1240.9	-4.8
50	1272.8	1283.2	+10.4
51	1311.3	1310.5	-0.7
52	1328.5	1335.5	+7.0
53	1359.0	1354.4	-4.6
54	1392.9	1387.9	-5.1
55	1416.5	1423.9	+7.4
56	1440.3	1446.4	+6.1
57	1444.3	1452.7	+8.4
58	1471.6	1482.2	+10.6
59	1486.7	1502.6	+15.8
60	1497.1	1511.4	+14.3
61	1512.3	1513.4	+1.0
62	1521.9	1535.7	+13.8
63	1529.4	1545.8	+16.4
64	1542.0	1576.1	+34.1
65	1633.8	1664.2	+30.4
66	1657.8	1684.0	+26.2
67	1658.4	1701.0	+42.6
68	1663.0	1707.0	+44.0
69	1668.8	1711.4	+42.6
70	3039.0	3074.9	+35.8
71	3087.1	3138.3	+51.3
72	3128.2	3175.5	+47.3
73	3176.0	3219.4	+43.4
74	3178.4	3221.6	+43.3
75	3181.0	3223.9	+42.9
76	3183.7	3227.1	+43.4
77	3193.5	3237.6	+44.1
78	3194.9	3237.9	+43.1
79	3195.5	3238.9	+43.4
80	3205.8	3249.3	+43.6
81	3207.3	3251.1	+43.8

Structure

2D depiction from the SMILES.

Status ladder

Listed
Cheap level done — 2026-09-20, ubuntu-32gb-hel1-10
Correction predicted — not yet: the learned layer is training
Spectrum predicted — not yet: the learned layer is training
Anchored
Validated

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Second route

Analytic Hessian (pyscf, grid 99/590) against the corpus finite differences: b3lyp max |Δω| 4 cm⁻¹; wb97x max |Δω| 19 cm⁻¹.

Provenance

Releases: layerA2_2026-09-23, layerA2_2026-09-23b, layerA2_2026-09-24
Entered the corpus as: substituted three- and four-ring cores, enumerated from the parents (layer A′) (layer A2)
Run: ubuntu-32gb-hel1-10, 2026-09-19 22:51:40 → 2026-09-20 00:56:38, 7498 s, peak 6.99 GB, deck 97ed2d67c66b
Imaginary modes: B3LYP 0, ωB97X 0
Source files: corpus factory · manifest